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                                                                    EXHIBIT 99.2



                            STOCK PURCHASE AGREEMENT


         STOCK PURCHASE AGREEMENT (this "Agreement"), dated as of September 13,
2004 between Central Bancorp, Inc., a Massachusetts corporation ("Central
Bancorp"), and the Central Co-operative Bank Employee Stock Ownership Trust (the
"ESOP," and together with Central Bancorp, the "Purchasers"), on the one hand,
and PL Capital, LLC ("PL Capital"), Financial Edge Fund, L.P., Financial
Edge-Strategic Fund, L.P., Goodbody/PL Capital, L.P., Goodbody/PL Capital, LLC,
Richard Lashley, John W. Palmer and Richard J. Fates on the other hand (each a
"Seller" and collectively, the "Sellers" or the "PL Capital Parties") on behalf
of themselves and their respective affiliates (the Purchasers and the PL Capital
Parties together, collectively, the "Parties").

         WHEREAS, each PL Capital Party owns that number of the issued and
outstanding shares of common stock, par value $1.00 per share ("Common Stock"),
of Central Bancorp, set forth opposite his or its name on Schedule A hereto
(such Seller's "Contract Shares");

         WHEREAS, the Purchasers desire to purchase from the Sellers, and each
Seller desires to sell to the Purchasers, all of such Seller's Contract Shares
on the terms and subject to the conditions set forth herein;

         NOW THEREFORE, the Purchasers and the Sellers agree as follows:

1.   PURCHASE AND SALE OF THE CONTRACT SHARES

     (a) Subject to the terms and conditions of this Agreement, including the
accuracy of the representations and warranties set forth herein, the ESOP agrees
to purchase from the Sellers, and the Sellers agrees to sell to the ESOP, 77,134
of such Sellers' Contract Shares at the Closing (as defined below).

     (b) Subject to the terms and conditions of this Agreement, including the
accuracy of the representations and warranties set forth herein, Central Bancorp
agrees to purchase from the Sellers, and the Sellers agree to sell to Central
Bancorp, the remaining 77,134 of such Sellers' Contract Shares at the Closing.

     (c) The purchase price for the Contract Shares is $33.25 per Contract
Share (the "Share Price").

     (d) At the Closing, each Seller shall deliver to the appropriate Purchaser,
in a form and in a manner reasonably acceptable to each Purchaser, all of such
Seller's Contract Shares being sold at such time, free and clear of all liens,
pledges, charges, equities, claims or other encumbrances, together with any
further documents or instruments, including, if appropriate, stock powers duly
endorsed in blank or stock transfer stamps affixed thereto, or certificates from


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broker-dealers previously holding liens on such shares or holding such shares
for a Seller, reasonably requested by each Purchaser.

     (e) At the Closing, the Purchaser purchasing Contract Shares from a Seller
shall pay by wire transfer to each such Seller an amount equal to the Share
Price multiplied by the number of such Seller's Contract Shares being sold to
such Purchaser.

2.   THE CLOSING

     (a) The Closing shall occur as soon as practicable but not later than five
days after satisfaction or waiver of all of the conditions set forth in Section
7 herein and shall be on such date and at such time and location as is mutually
agreed by the Company and PL Capital.

     (b) Upon payment by the Purchasers to each Seller of the Share Price for
such Seller's Contract Shares and delivery by each Seller of his or its Contract
Shares to the Purchaser the Closing shall have occurred and the purchase and
sale of the Sellers' Contract Shares shall be deemed to be complete.

3.   STANDSTILL

     The PL Capital Parties each agree that, for a period of time commencing at
the Closing and continuing for five years following the Closing (the "Standstill
Period"), they and their affiliates and associates (as defined in Rule 12b-2
promulgated pursuant to the Securities Exchange Act of 1934, as amended (the
"Exchange Act")) will not (and they will not assist or encourage others to),
directly or indirectly, in any manner, without prior written approval of the
Board of Directors of Central Bancorp:

     (a) acquire, offer to acquire, solicit an offer to sell or agree to acquire
directly or indirectly, alone or in concert with others, by purchase, gift or
otherwise, any direct or indirect beneficial ownership (within the meaning of
Rule 13d-3 under the Exchange Act) or any direct or indirect interest in any
securities or direct or indirect rights, warrants or options to acquire, or
securities convertible into or exchangeable for (collectively, an
"Acquisition"), any securities of Central Bancorp ("Securities");

     (b) make, or in any way participate in, directly or indirectly, alone or in
concert with others, any "solicitation" of "proxies" to vote (as such terms are
used in the proxy rules of the Securities and Exchange Commission promulgated
pursuant to Section 14 of the Exchange Act) or seek to advise or influence in
any manner whatsoever any person with respect to the voting of any voting
securities of Central Bancorp;

     (c) form, join or in any way participate in a "group" within the meaning of
Section 13(d)(3) of the Exchange Act with respect to any voting Securities of
Central Bancorp;


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     (d) acquire, offer to acquire or agree to acquire, directly or indirectly,
alone or in concert with others, by purchase, exchange or otherwise, (i) any of
the assets, tangible and intangible, of Central Bancorp or (ii) direct or
indirect rights, warrants or options to acquire any assets of Central Bancorp;

     (e) arrange, or in any way participate, directly or indirectly, in any
financing for the purchase of any Securities or securities convertible or
exchangeable into or exercisable for any Securities or assets of Central
Bancorp;

     (f) otherwise act, alone or in concert with others to seek to offer to
Central Bancorp or any of its stockholders any business combination,
restructuring, recapitalization or similar transaction to or with Central
Bancorp or otherwise seek, alone or in concert with others to control or change
the management, board of directors or policies of Central Bancorp or nominate
any person as a director of Central Bancorp who is not nominated by the then
incumbent directors, or propose any matter to be voted upon by the stockholders
of Central Bancorp; or

     (g) announce an intention to do, or enter into any arrangement or
understanding with others to do, any of the actions restricted or prohibited
under clauses (a) through (f) of this Paragraph 2, or publicly announce or
disclose any request to be excused from any of the foregoing obligations of this
Paragraph 2.

4.   DISCLOSURE OF THIS AGREEMENT

     The parties contemplate that PL Capital will file a Schedule 13D amendment
attaching this Agreement, that Central Bancorp will file a Form 8-K attaching
this Agreement and that there will be no other public comments (except as
required by applicable SEC regulations) by the Parties regarding this Agreement
other than a press release by Central Bancorp factually summarizing this
Agreement and referring to the Form 8-K filing.

5.   REPRESENTATIONS AND WARRANTIES OF EACH SELLER

     The Sellers hereby represent and warrant, jointly and severally, to the
Purchaser as of the date of this Agreement and the Closing:

     (a) Each Seller has the requisite capacity, power and authority to enter
into this Agreement and to consummate the transactions contemplated hereby.

     (b) The execution and delivery of this Agreement by each Seller and the
sale and delivery of the Contract Shares hereunder have been duly authorized by
all necessary actions on the part of such Seller and any necessary third party
(including any consultation, approval or other action by or with any other
person or governmental entity), and will not conflict with or result in a breach
or violation of any of the terms or provisions of its certificate of
incorporation or by laws (if it is a corporation) or equivalent constituent
documents or result in the breach or violation of any of the terms or provisions
of, or constitute a default under, any indenture,


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mortgage, deed of trust, loan agreement or any other agreement or instrument to
which it is a party or by which it is bound or to which any of its properties or
assets is subject, nor will any such action result in any violation of the
provisions of any statute or any order, rule or regulation of any court or
governmental agency or body having jurisdiction over it or its property.

     (c) This Agreement has been duly executed and delivered by each Seller and
constitutes a valid and binding obligation of such Seller, enforceable against
the Seller in accordance with its terms, subject to bankruptcy, insolvency,
fraudulent transfer, reorganization, moratorium and similar laws of general
applicability relating to or affecting creditors' rights and to general equity
principles (regardless of whether enforcement is sought in a proceeding in
equity or at law).

     (d) Each Seller has record and beneficial ownership of and good and valid
title to such Seller's Contract Shares, and such ownership and title are free
and clear of all liens, pledges, charges, equities, claims or other
encumbrances.

     (e) Upon each delivery of the Contract Shares hereunder and payment
therefor pursuant hereto, good and valid title to such Contract Shares, free and
clear of all liens, pledges, charges, equities, claims and encumbrances, will
pass to the Purchasers.

     (f) Each Seller beneficially owns only those Common Shares identified as
Contract Shares with respect to such Seller on Schedule A hereto, and such
Seller does not hold or beneficially own any other securities of Central Bancorp
other than such Contract Shares.

     (g) Each Seller is not participating with any other person, other than the
other Sellers, in any "group", as such term is used in Rule 13D under the
Exchange Act, with respect to any security of Purchaser.

     (h) There is not pending or, to Seller's knowledge, threatened against
Seller any action, suit or proceeding at law or in equity before any court,
tribunal, governmental body, agency or official or any arbitrator that might
affect the legality, validity or enforceability against such Seller of this
Agreement or such Seller's ability to perform such Seller's obligations
hereunder.

     (i) No person or entity acting on behalf or under the authority of Seller
is or will be entitled to any broker's, finder's, or similar fee or commission
in connection with the transactions contemplated by this Agreement.

6.   REPRESENTATIONS AND WARRANTIES OF THE PURCHASERS

     Each Purchaser represents and warrants, solely for itself and not on behalf
of or with respect to the other Purchaser, to each of the Sellers as of the date
of this Agreement and the Closing as follows:


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     (a) Central Bancorp is duly organized and is validly existing under the
laws of Massachusetts. The trust included in the ESOP is duly formed under the
laws of the Commonwealth of Massachusetts and under the Employee Retirement
Income Security Act of 1974, as amended.

     (b) Purchaser has the requisite power and authority to enter into this
Agreement and to consummate the transactions contemplated hereby.

     (c) Except for the regulatory review and ESOP lender consent contemplated
by Paragraphs 7(a)(3) and (4) of this Agreement, the execution and delivery of
this Agreement by each Purchaser has been duly authorized by all necessary
actions on the part of such Purchaser and any necessary third party (including
any consultation, approval or other action by or with any other person or
governmental entity), and will not conflict with or result in a breach or
violation of any of the terms or provisions of its articles of organization or
bylaws, in the case of Central Bancorp, or plan or trust documents, in the case
of the ESOP, or result in the breach or violation of any of the terms or
provisions of, or constitute a default under, any indenture, mortgage, deed of
trust, loan agreement or any other agreement or instrument to which it is a
party or by which it is bound or to which any of its properties or assets is
subject, nor will any such action result in any violation of the provisions of
any statute or any order, rule or regulation of any court or governmental agency
or body having jurisdiction over it or its property.

     (d) This Agreement has been duly executed and delivered by each Purchaser
and constitutes a valid and binding obligation of the Purchaser, enforceable
against the Purchaser in accordance with its terms, subject to bankruptcy,
insolvency, fraudulent transfer, reorganization, moratorium and similar laws of
general applicability relating to or affecting creditors' rights and to general
equity principles (regardless of whether enforcement is sought in a proceeding
in equity or at law).

     (e) There is not pending or, to each Purchaser's knowledge, threatened
against such Purchaser any action, suit or proceeding at law or in equity before
any court, tribunal, governmental body, agency or official or any arbitrator
that might affect the legality, validity or enforceability against it of this
Agreement or its ability to perform its obligations hereunder.

     (f) No person or entity acting on behalf or under the authority of each
Purchaser is or will be entitled to any broker's, finder's, or similar fee or
commission in connection with the transactions contemplated by this Agreement.

7.   CONDITIONS TO THE OBLIGATIONS OF PURCHASERS

     (a) CONDITIONS TO THE OBLIGATIONS OF PURCHASERS. The obligations of the
respective Purchasers to consummate the transactions contemplated by this
Agreement are subject to the satisfaction at or prior to the Closing of the
following conditions:



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                  (1) Trust Preferred Offering. Central Bancorp shall have
                      ------------------------
completed the offering and sale of at least $5.1 million in trust preferred
securities.

                  (2) Regulatory Review. Any review of the transactions
                      -----------------
contemplated by this Agreement required under law, regulations or policies by
regulatory authorities with jurisdiction over Central Bancorp, Central
Cooperative Bank (the "Bank"), the ESOP and their affiliates shall have been
completed, and no such regulatory authority shall have advised Central Bancorp,
the Bank or the ESOP that it may not proceed to consummate the transactions
contemplated by this Agreement.

                  (3) ESOP Lender Consent. Central Bancorp and the ESOP shall
                      -------------------
have obtained the written consent to the transactions contemplated by this
Agreement from the lender with a loan presently outstanding to the ESOP (the
"Lender") pursuant to such Lender's agreement, dated October 16, 2003, among
Gregory W. Boulos and Paul E. Bulman as trustees of the ESOP trust, Central
Bancorp and the Lender.

                  (4) Representations and Warranties. The representations and
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warranties of the PL Capital parties contained in Paragraph 5 of this Agreement
shall be true and correct, in all material respects, on and as of the Closing
with the same effect as though made on and as of the Closing.

                  (5) Director Resignations. Richard J. Lashley and Richard J.
                      ---------------------
Fates shall have submitted letters resigning from all positions on the boards of
directors and committees of the boards of directors of Central Bancorp and
Central Cooperative Bank (the "Bank"), effective at the Closing.

         (b) CONDITIONS TO THE OBLIGATIONS OF SELLERS. The obligations of the
respective Sellers to consummate the transactions contemplated by this Agreement
are subject to the satisfaction at or prior to the Closing of the following
condition:

                  (1) Representations and Warranties. The representations and
                      ------------------------------
warranties of the Purchasers parties contained in Paragraph 6 of this Agreement
shall be true and correct, in all material respects, on and as of the Closing
with the same effect as though made on and as of the Closing.

8.   TERMINATION

         This Agreement may be terminated at any time prior to the Closing (i)
by mutual consent in writing of the Parties, (ii) by either the Purchasers on
the one hand or the Sellers on the other hand in the event the Closing shall not
have occurred within 60 days following the date of this Agreement, (iii) by the
Purchasers in the event any of the conditions set forth in Paragraph 7(a) herein
is not satisfied as of the Closing, or (iv) by the Sellers in the event the
condition set forth in Paragraph 7(b) herein is not satisfied as of the Closing.


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9.   NON-DISPARAGEMENT

         During the Standstill Period, the PL Capital Parties agree not to
disparage either of the Purchasers or any officers, directors (including
director nominees) or employees of Central Bancorp or the Bank in any public
forum, and the Purchasers agree not to disparage any of the PL Capital Parties
or any officers or employees of PL Capital in any public forum.

10.  MISCELLANEOUS

     (a) ENTIRE AGREEMENT. This Agreement constitutes the entire agreement and
understanding among each of the Purchasers and each of the Sellers with respect
to the subject matter hereof and supersedes all other prior agreements,
understandings and arrangements, whether oral or written, among the parties
hereto. Notwithstanding the preceding sentence, the Parties contemplate that the
Agreement dated August 4, 2003 by and between the Central Bancorp Parties, as
defined therein, and the PL Capital Parties shall remain in effect and shall
continue in effect in accordance with its terms.

     (b) EXPENSES. Each party hereto shall be responsible for and shall pay its
own costs and expenses, including attorneys' fees and accountants' fees and
expenses, incurred in connection with the negotiation, execution and delivery of
this Agreement. Each Seller shall pay any transfer taxes imposed on transferors
payable in connection with the sale of his or its Contract Shares to be sold by
him or it hereunder.

     (c) GOVERNING LAW. This Agreement shall be governed by, and construed in
accordance with, the laws of the Commonwealth of Massachusetts applicable to
contracts made and to be performed in such Commonwealth without regard to the
conflict of law principles thereof.

     (d) SUCCESSORS AND ASSIGNS. This Agreement shall benefit and bind the
successors and permitted assigns of the parties hereto. Any assignment of this
Agreement by any party without the prior written consent of each of the other
parties shall be void AB INITIO.

     (e) AMENDMENTS. This Agreement may only be amended or modified by a written
instrument signed by all of the Parties hereto.

     (f) WAIVERS. No waiver of any provision of this Agreement by any party
shall be deemed to be a continuing waiver of any provision of this Agreement by
such party.

     (g) EQUITABLE RELIEF.  The parties hereby expressly recognize and
acknowledge that immediate, extensive and irreparable damage would result in the
event the covenants and agreements in this Agreement are not specifically
enforced. Therefore, in addition to, and not in limitation of, any other remedy
available to the Purchasers and the Sellers, the respective rights of the
Purchasers and Sellers and obligations of the Sellers and Purchasers,
respectively, shall be


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enforceable in a court of equity by decree of specific performance and
appropriate injunctive relief may be applied for and granted in connection
therewith.

     (h) COUNTERPARTS; DELIVERY. This Agreement may be executed in any number of
separate counterparts, each such counterpart being deemed to be an original
instrument, and all such counterparts shall together constitute the same
agreement. Delivery may be effected via facsimile.





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         IN WITNESS WHEREOF, the Purchaser and each Seller have executed this
Agreement on the date set forth below.

Dated:   September 13, 2004

For:     PL Capital, LLC                       For Central Bancorp, Inc.:
         Financial Edge Fund, L.P.
         Financial Edge-Strategic Fund, L.P.
         Goodbody/PL Capital, L.P.             /s/ John D. Doherty
         Goodbody/PL Capital, LLC              ---------------------------------
                                               By: John D. Doherty
                                                   President


/s/ Richard Lashley                            For the Central Co-operative Bank
- ----------------------------------             Employee Stock Ownership Trust:
By:   Richard Lashley
      Managing Member
                                               /s/ Gregory W. Boulos
                                               ---------------------------------
/s/ John W. Palmer                             By: Gregory W. Boulos, Trustee
- -----------------------------------
By:   John W. Palmer
      Managing Member                          /s/ Paul E. Bulman
                                               ---------------------------------
                                               By: Paul E. Bulman, Trustee

For Richard Lashley:

/s/ Richard Lashley
- ------------------------------------
Richard Lashley


For John W. Palmer:

/s/ John W. Palmer
- -------------------------------------
John W. Palmer


For Richard J. Fates:

/s/ Richard J. Fates
- -------------------------------------
Richard J. Fates



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